diff --git a/compiler/src/prog8/ast/expressions/AstExpressions.kt b/compiler/src/prog8/ast/expressions/AstExpressions.kt
index 1f48adc9a..a5cd21e2e 100644
--- a/compiler/src/prog8/ast/expressions/AstExpressions.kt
+++ b/compiler/src/prog8/ast/expressions/AstExpressions.kt
@@ -43,6 +43,23 @@ sealed class Expression: Node {
                 (other is ArrayIndexedExpression && other.identifier.nameInSource == identifier.nameInSource
                         && other.arrayspec.index isSameAs arrayspec.index)
             }
+            is DirectMemoryRead -> {
+                (other is DirectMemoryRead && other.addressExpression isSameAs addressExpression)
+            }
+            is TypecastExpression -> {
+                (other is TypecastExpression && other.implicit==implicit && other.type==type && other.expression isSameAs expression)
+            }
+            is AddressOf -> {
+                (other is AddressOf && other.identifier.nameInSource == identifier.nameInSource)
+            }
+            is RangeExpr -> {
+                (other is RangeExpr && other.from==from && other.to==to && other.step==step)
+            }
+            is FunctionCall -> {
+                (other is FunctionCall && other.target.nameInSource == target.nameInSource
+                        && other.args.size == args.size
+                        && other.args.zip(args).all { it.first isSameAs it.second } )
+            }
             else -> other==this
         }
     }
diff --git a/compiler/src/prog8/optimizer/ExpressionSimplifier.kt b/compiler/src/prog8/optimizer/ExpressionSimplifier.kt
index cf8739e69..38046e555 100644
--- a/compiler/src/prog8/optimizer/ExpressionSimplifier.kt
+++ b/compiler/src/prog8/optimizer/ExpressionSimplifier.kt
@@ -40,13 +40,6 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             // remove the sub-typecast if its datatype is larger than the outer typecast
             if(subTypecast.type largerThan typecast.type) {
                 mods += IAstModification.ReplaceNode(typecast.expression, subTypecast.expression, typecast)
-            } else {
-                if(subTypecast.type == DataType.UBYTE && typecast.type == DataType.UWORD) {
-                    // (X as ubyte) as uword  ->  X & 255
-                    // TODO don't optimize this because the asm code generated by it is worse...
-//                    val and255 = BinaryExpression(subTypecast.expression, "&", NumericLiteralValue.optimalInteger(255, subTypecast.position), subTypecast.position)
-//                    mods += IAstModification.ReplaceNode(typecast, and255, parent)
-                }
             }
         } else {
             if (typecast.expression.inferType(program).istype(typecast.type)) {
diff --git a/compiler/src/prog8/optimizer/StatementOptimizer.kt b/compiler/src/prog8/optimizer/StatementOptimizer.kt
index be6794d97..50804e93f 100644
--- a/compiler/src/prog8/optimizer/StatementOptimizer.kt
+++ b/compiler/src/prog8/optimizer/StatementOptimizer.kt
@@ -368,11 +368,12 @@ internal class StatementOptimizer(private val program: Program,
                     }
                 }
             }
-            if(binExpr.right isSameAs assignment.target) {
-                if(binExpr.operator in setOf("+", "*", "&", "|")) {
-                    // associative operator, swap the operands so that the assignment target is first (left)
+
+            if(binExpr.operator in associativeOperators && binExpr.right isSameAs assignment.target) {
+                // associative operator, swap the operands so that the assignment target is first (left)
+                // unless the other operand is the same in which case we don't swap (endless loop!)
+                if (!(binExpr.left isSameAs binExpr.right))
                     return listOf(IAstModification.SwapOperands(binExpr))
-                }
             }
 
         }
diff --git a/examples/test.p8 b/examples/test.p8
index 631dfd690..def5f62be 100644
--- a/examples/test.p8
+++ b/examples/test.p8
@@ -7,18 +7,22 @@ main {
 
     sub start() {
 
-        ;@($d020) += @($d020)        ; TODO fix compiler hang
+        @($d020) += @($d020)        ; TODO fix compiler hang
 
-        ubyte A = 10
-        @($c00a) = $4a
-        @($c000+A) ++       ; TODO implement this
+        ubyte A
 
-        c64scr.print_ubhex(@($c00a), true)
-        c64.CHROUT('\n')
-        @($c000+A) --      ; TODO implement this
+        A = 44+A
 
-        c64scr.print_ubhex(@($c00a), true)
-        c64.CHROUT('\n')
+;        ubyte A = 10
+;        @($c00a) = $4a
+;        @($c000+A) ++       ; TODO implement this
+;
+;        c64scr.print_ubhex(@($c00a), true)
+;        c64.CHROUT('\n')
+;        @($c000+A) --      ; TODO implement this
+;
+;        c64scr.print_ubhex(@($c00a), true)
+;        c64.CHROUT('\n')
 
     }
 }